Question: I want either a whole house or an undercounter water filtration system that filters not only lead, chlorine and the usual household concerns, but also fluoride. And, I want the system to be a direct line system, not a tank system, e.g., not a reverse osmosis system. I realize that the price relatively may be expensive. Can you please direct me to someone?
Much appreciated.

Philip McGarry, Sunnyvale, Calif.

Answer: Activated carbon filters will readily take out chlorine, and they often contain special adsorbents to remove lead and other specific heavy metals. For removal of fluoride, if you chose not to use a reverse osmosis system, you can use a special adsorbent resin to accomplish this, such as activated alumina. The problem with using any of these adsorbents is that you can never be sure when they quit working. Your local water treatment dealer should be able to supply you with these systems.